Filled polyurethane composites with size-graded fillers

ABSTRACT

Polyurethane composites and methods of preparing polyurethane composites are described herein. The polyurethane composite can comprise (a) a polyurethane formed by the reaction of (i) one or more isocyanates selected from the group consisting of diisocyanates, polyisocyanates, and mixtures thereof, and (ii) one or more polyols; (b) fly ash comprising 50% or greater by weight, fly ash particles having a particle size of from 0.2 micron to 100 microns; and (c) a coarse filler material comprising 80% or greater by weight, filler particles having a particle size of from greater than 250 microns to 10 mm. The coarse filler material can be present in the composite in an amount of from 1% to 40% by weight, based on the total weight of the composite. The weight ratio of the fly ash to the coarse filler material can be from 9:1 to 200:1.

FIELD OF THE DISCLOSURE

This disclosure relates generally to polyurethane composites, moreparticularly, to the use of size-graded fillers including a fine fillersuch as fly ash and a coarse filler in polyurethane composites.

BACKGROUND OF THE DISCLOSURE

Polymeric composites that contain organic and/or inorganic fillermaterials have become desirable for a variety of uses because of theirexcellent mechanical properties and weathering stability. In general,the superior properties of the polymeric composites are achieved throughuse of the polymer as the matrix material that acts as a glue withenhanced flexural properties or as a fibrous component providingreinforcement and improved tensile properties. The inorganic materialimparts various properties of rigidity, toughness, hardness, opticalappearance and interaction with electromagnetic radiation, density, andmany other physical and chemical attributes. A proper blend of polymericand inorganic materials provides for a composite with optimal propertiesat a desirably low cost.

Polyurethane composites composed of a polyurethane binder and fly ashfiller with glass fiber reinforcement have been shown to be very useful.Specific uses of such composites include applications as interior andexterior cladding on buildings. However, one challenge for highly-filledfiller-polyurethane composites is that it is very difficult to improvethe mechanical performance of such materials without incurringsignificant costs. Another challenge is that there exists a thresholdfor the total content of the fly ash filler and reinforcement materialsthat can be incorporated into the composites. In particular, raising thecontent of fly ash filler and/or reinforcement materials can greatlyincrease the viscosity of the polyurethane mixture and eventually makesuch systems difficult to process and manufacture into gross and netshapes. There is a need to improve the properties of filled composites.The compositions and methods described herein address these and otherneeds.

SUMMARY OF THE DISCLOSURE

Polyurethane composites and methods of preparing polyurethane compositesare described herein. The polyurethane composites can comprise (a) apolyurethane formed by the reaction of (i) one or more isocyanatesselected from the group consisting of diisocyanates, polyisocyanates,and mixtures thereof, and (ii) one or more polyols; (b) fly ashcomprising 50% or greater by weight, fly ash particles having a particlesize of from 0.2 micron to 100 microns; and (c) a coarse filler materialcomprising 80% or greater by weight, filler particles having a particlesize of from greater than 250 microns to 10 mm.

The polyurethane can be present in an amount of from 15% to 60% byweight, based on the total weight of the composite. In some examples,the polyurethane can be present in an amount of from 15% to 40% byweight, based on the total weight of the composite. In some embodiments,50% or more of the one or more polyols can have a hydroxyl number of 250mg KOH/g or greater. In some embodiments, 50% or more of the one or morepolyols can include 75% or more primary hydroxyl groups based on thetotal number of hydroxyl groups in the polyol. The one or more polyolscan comprise an aromatic polyester polyol, an aromatic polyether polyol,or a combination thereof.

The coarse filler material can be present in the composite in an amountof from 1% to 40% (for example, 1 to 30%) by weight, based on the totalweight of the composite. In some embodiments, 80% or greater by weightof the coarse filler material comprises filler particles having particlesize of from greater than 250 microns to 1 mm, for example, 300 micronsto 500 microns. Suitable coarse filler materials can include silicasand, silica fume, cement, slag, metakaolin, talc, mica, wollastonite,limestone, calcium carbonate, perlite, clay, shale, ceramic, glass, seedhull, organic waste, or combinations thereof. In some examples, thecoarse filler material includes expanded glass or sand. In someembodiments, the coarse filler material can be coated with an agentselected from surfactants, bonding agents, pigments, and combinationsthereof.

Fly ash can be present in the composite in an amount of from 20% to 90%(for example, 20% to 80% or 50% to 80%) by weight, based on the totalweight of the composite. In some examples, fly ash can be present in thecomposite in an amount of from 20% to 80% or 50% to 80% by weight, basedon the total weight of the composite. In some embodiments, the fly ashcan be Class C fly ash. In some examples, the fly ash can have aparticle size distribution comprising a first mode having a medianparticle diameter from 0.3 micron to 1 micron, a second mode having amedian particle diameter from 10 microns to 25 microns, and a third modehaving a median particle diameter from 40 microns to 80 microns.

The weight ratio of the fly ash to the coarse filler material can befrom 9:1 to 200:1, such as from 9:1 to 150:1.

The polyurethane composite can further comprise a fiber material. Thefiber material can be present in an amount of from 1% to 20% by weight,based on the total weight of the composite. Examples of suitable fibermaterials include polyacrylonitrile fibers, polyamide fibers, polyesterfibers, glass fibers, mineral wool, rayon, cellulose, wood fibers, sawdust, wood shavings, cotton, lint, polypropylene fibers, polyethylenefibers, polyacrylic fibers, or combinations thereof. In someembodiments, the fiber material can include a plurality of glass fibers.The glass fibers can have an average length of 1 mm or greater, forexample, from 1.5 mm to 30 mm.

In some embodiments, the polyurethane composite can be foamed. Thedensity of the polyurethane composites described herein can be from 5lb/ft³ to 70 lb/ft³. The composite can have a flexural strength of 300psi or greater, as measured by ASTM C1185.

Building materials comprising the polyurethane composites describedherein are disclosed. The building material can include sidingmaterials, carpet backings, building panels, sheets, architecturalmoldings, sound barriers, thermal barriers, insulation, wall board,ceiling tiles, ceiling boards, soffit, and roofing materials.

Methods of making the polyurethane composites described herein aredisclosed. The method can include (a) mixing (1) one or more isocyanatesselected from the group consisting of diisocyanates, polyisocyanates,and mixtures thereof, (2) one or more polyols, (3) fly ash comprising50% or greater by weight, fly ash particles having a particle size offrom 0.2 micron to 100 microns, and (4) a coarse filler materialcomprising 80% or greater by weight, filler particles having a particlesize of from 250 microns to 10 mm to form a mixture; and (b) allowingthe one or more isocyanates and the one or more polyols to react in thepresence of the fly ash and the coarse filler material to form thepolyurethane composite. In some embodiments, the polyurethane mixturecan further include a catalyst.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing the packing density of blends of fly ash andcoarse filler materials as a function of the coarse filler content.

FIG. 2 is a graph showing the viscosity of a filled polyurethanecomposition as a function of the coarse filler material content. Thecoarse filler materials include Geotex 30-50, Geotex 40-200, and GeotexFX.

FIG. 3 is a graph showing the flexural strength of polyurethanecomposites as a function of density.

FIG. 4 is a graph showing the flexural strength of a fly ash filledpolyurethane composite as a function of fiber glass content.

DETAILED DESCRIPTION

Polyurethane composites and methods of preparing polyurethane compositesare described herein. The polyurethane composites can comprise apolyurethane formed using highly reactive systems such as highlyreactive polyols, isocyanates, or both.

Isocyanates suitable for use in the polyurethane composite describedherein include one or more monomeric or oligomeric poly- ordi-isocyanates. The monomeric or oligomeric poly- or di-isocyanateinclude aromatic diisocyanates and polyisocyanates. The isocyanates canalso be blocked isocyanates or pre-polymer isocyanates. An example of auseful diisocyanate is methylene diphenyl diisocyanate (MDI). UsefulMDI's include MDI monomers, MDI oligomers, and mixtures thereof.

Further examples of useful isocyanates include those having NCO (i.e.,the reactive group of an isocyanate) contents ranging from about 25% toabout 35% by weight. Examples of useful isocyanates are found, forexample, in Polyurethane Handbook: Chemistry, Raw Materials, ProcessingApplication, Properties, 2^(nd) Edition, Ed: Gunter Oertel;Hanser/Gardner Publications, Inc., Cincinnati, Ohio, which is hereinincorporated by reference. Suitable examples of aromatic polyisocyanatesinclude 2,4- or 2,6-toluene diisocyanate, including mixtures thereof;p-phenylene diisocyanate; tetramethylene and hexamethylenediisocyanates; 4,4-dicyclohexylmethane diisocyanate; isophoronediisocyanate; 4,4-phenylmethane diisocyanate; polymethylenepolyphenylisocyanate; and mixtures thereof. In addition, triisocyanatesmay be used, for example, 4,4,4-triphenylmethane triisocyanate;1,2,4-benzene triisocyanate; polymethylene polyphenyl polyisocyanate;methylene polyphenyl polyisocyanate; and mixtures thereof. Suitableblocked isocyanates are formed by the treatment of the isocyanatesdescribed herein with a blocking agent (e.g., diethyl malonate,3,5-dimethylpyrazole, methylethylketoxime, and caprolactam). Isocyanatesare commercially available, for example, from Bayer Corporation(Pittsburgh, Pa.) under the trademarks MONDUR and DESMODUR. Otherexamples of suitable isocyanates include MONDUR MR Light (BayerCorporation; Pittsburgh, Pa.), PAPI 27 (Dow Chemical Company; Midland,Mich.), Lupranate M20 (BASF Corporation; Florham Park, N.J.), LupranateM70L (BASF Corporation; Florham Park, N.J.), Rubinate M (HuntsmanPolyurethanes; Geismar, La.), Econate 31 (Ecopur Industries), andderivatives thereof.

The average functionality of isocyanates useful with the compositesdescribed herein can be between about 1.5 to about 5. Further, examplesof useful isocyanates include isocyanates with an average functionalityof about 2 to about 4.5, about 2.2 to about 4, about 2.4 to about 3.7,about 2.6 to about 3.4, and about 2.8 to about 3.2.

The one or more polyols for use in the polyurethane composite caninclude polyester polyols, polyether polyols, or combinations thereof.In some embodiments, the one or more polyols can include 50% or more ofone or more highly reactive (i.e., first) polyols. For example, the oneor more polyols can include greater than 55%, greater than 60%, greaterthan 65%, greater than 70%, greater than 75%, greater than 80%, greaterthan 85%, greater than 90%, greater than 95%, or 100% of one or morehighly reactive polyols.

In some embodiments, the one or more highly reactive polyols can includepolyols having a hydroxyl number of greater than 250. For example, thehydroxyl number can be greater than 275, greater than 300, greater than325, greater than 350, greater than 375, greater than 400, greater than425, greater than 450, greater than 475, greater than 500, greater than525, greater than 550, greater than 575, greater than 600, greater than625, greater than 650, greater than 675, greater than 700, greater than725, or greater than 750.

In some embodiments, the one or more highly reactive polyols can includepolyols having a primary hydroxyl number of greater than 250. As usedherein, the primary hydroxyl number is defined as the hydroxyl numbermultiplied by the percentage of primary hydroxyl groups based on thetotal number of hydroxyl groups in the polyol. For example, the primaryhydroxyl number can be greater than 255, greater than 260, greater than265, greater than 270, greater than 275, greater than 280, greater than285, greater than 290, or greater than 295.

In some embodiments, the one or more highly reactive polyols include alarge number of primary hydroxyl groups (e.g. 75% or more) based on thetotal number of hydroxyl groups in the polyol. For example, the highlyreactive polyols can include 80% or more, 85% or more, 90% or more, 95%or more, or 100% of primary hydroxyl groups. The number of primaryhydroxyl groups can be determined using fluorine NMR spectroscopy asdescribed in ASTM D4273, which is hereby incorporated by reference inits entirety.

In some embodiments, the one or more highly reactive polyols can includea Mannich polyol. Mannich polyols are the condensation product of asubstituted or unsubstituted phenol, an alkanolamine, and formaldehyde.Mannich polyols can be prepared using methods known in the art. Forexample, Mannich polyols can be prepared by premixing the phenoliccompound with a desired amount of the alkanolamine, and then slowlyadding formaldehyde to the mixture at a temperature below thetemperature of Novolak formation. At the end of the reaction, water isstripped from the reaction mixture to provide a Mannich base. See, forexample, U.S. Pat. No. 4,883,826, which is incorporated herein byreference in its entirety. The Mannich base can then be alkoxylated toprovide a Mannich polyol.

The substituted or unsubstituted phenol can include one or more phenolichydroxyl groups. In certain embodiments, the substituted orunsubstituted phenol includes a single hydroxyl group bound to a carbonin an aromatic ring. The phenol can be substituted with substituentswhich do not undesirably react under the conditions of the Mannichcondensation reaction, a subsequent alkoxylation reaction (ifperformed), or the preparation of polyurethanes from the final product.Examples of suitable substituents include alkyl (e.g., a C₁-C₁₈ alkyl,or a C₁-C₁₂ alkyl), aryl, alkoxy, phenoxy, halogen, and nitro groups.

Examples of suitable substituted or unsubstituted phenols that can beused to form Mannich polyols include phenol, o-, p-, or m-cresols,ethylphenol, nonylphenol, dodecylphenol, p-phenylphenol, variousbisphenols including 2,2-bis(4-hydroxyphenyl)propane (bisphenol A),β-naphthol, β-hydroxyanthracene, p-chlorophenol, o-bromophenol,2,6-dichlorophenol, p-nitrophenol, 4- or 2-nitro-6-phenylphenol,2-nitro-6- or 4-methylphenol, 3,5-dimethylphenol, p-isopropylphenol,2-bromo-6-cyclohexylphenol, and combinations thereof. In someembodiments, the Mannich polyol is derived from phenol or a monoalkylphenols (e.g., a para-alkyl phenols). In some embodiments, the Mannichpolyol is derived from a substituted or unsubstituted phenol selectedfrom the group consisting of phenol, para-n-nonylphenol, andcombinations thereof.

The alkanolamine used to produce the Mannich polyol can include amonoalkanolamine, a dialkanolamine, or combinations thereof. Examples ofsuitable monoalkanolamines include methylethanolamine,ethylethanolamine, methylisopropanolamine, ethylisopropanolamine,methyl-2-hydroxybutylamine, phenylethanolamine, ethanolamine,isopropanolamine, and combinations thereof. Exemplary dialkanolaminesinclude diisopropanolamine, ethanolisopropanolamine,ethanol-2-hydroxybutylamine, isopropanol-2-hydroxybutylamine,isopropanol-2-hydroxyhexylamine, ethanol-2-hydroxyhexylamine, andcombinations thereof. In certain embodiments, the alkanolamine isselected from the group consisting of diethanolamine,diisopropanolamine, and combinations thereof.

Any suitable alkylene oxide or combination of alkylene oxides can beused to form the Mannich polyol. In some embodiments, the alkylene oxideis selected from the group consisting of ethylene oxide, propyleneoxide, butylene oxide, and combinations thereof. In certain embodiments,the Mannich polyol is alkoxylated with from 100% to about 80% propyleneoxide and from 0 to about 20 wt. % ethylene oxide.

Mannich polyols are known in the art, and include, for example, ethyleneand propylene oxide-capped Mannich polyols sold under the trade namesCARPOL® MX-425 and CARPOL® MX-470 (Carpenter Co., Richmond, Va.).

In some embodiments, the one or more first polyols can include anaromatic polyester polyol, an aromatic polyether polyol, or acombination thereof. In some embodiments, the one or more first polyolsinclude an aromatic polyester polyol such as those sold under the TEROL®trademark (e.g., TEROL® 198).

Examples of highly reactive polyols also include Pel-Soy 744 and Pel-SoyP-750, soybean oil based polyols commercially available from PelronCorporation; Agrol Diamond, a soybean oil based polyol commerciallyavailable from BioBased Technologies; Ecopol 122, Ecopol 131 and Ecopol132, soybean oil polyols formed using polyethylene terephthalate andcommercially available from Ecopur Industries; Stepanpol PD-110 LV andPS 2352, polyols based on soybean oil, diethylene glycol and phthallicanhydride and commercially available from Stepan Company; Voranol 280,360 and WR2000, polyether polyols commercially available from DowChemical Company; Honey Bee HB-530, a soybean oil-based polyolcommercially available from MCPU Polymer Engineering; Renewpol,commercially available from Styrotech Industries (Brooklyn Park, Minn.);JeffAdd B 650, a 65% bio-based content (using ASTM D6866-06) additivebased on soybean oil commercially available from Huntsman Polyurethanes;Jeffol SG 360, a sucrose and glycerin-based polyol commerciallyavailable from Huntsman Polyurethanes; and derivatives thereof. Forexample, Ecopol 131 is a highly reactive aromatic polyester polyolcomprising 80% primary hydroxyl groups, a hydroxyl number of 360-380 mgKOH/g, i.e., and a primary hydroxyl number of 288-304 mg KOH/g.

The one or more polyols for use in the polyurethane composites caninclude one or more plant-based polyols. In some embodiments, theplant-based polyols are highly reactive polyols. The one or moreplant-based polyols useful in the polyurethane composites can includepolyols containing ester groups that are derived from plant-based fatsand oils. Accordingly, the one or more plant-based polyols can containstructural elements of fatty acids and fatty alcohols. Startingmaterials for the plant-based polyols of the polyurethane component caninclude fats and/or oils of plant-based origin with preferablyunsaturated fatty acid residues. The one or more plant-based polyolsuseful with the polyurethane composites include, for example, castoroil, coconut oil, corn oil, cottonseed oil, lesquerella oil, linseedoil, olive oil, palm oil, palm kernel oil, peanut oil, sunflower oil,tall oil, and mixtures thereof. In some embodiments, the one or morepolyols are non-plant-based polyols.

In some embodiments, the one or more polyols include a less reactivepolyol. For example, the polyurethane composite can be produced from oneor more less reactive polyols in addition to one or more highly reactivepolyols. Less reactive polyols can have lower hydroxyl numbers, lowernumbers of primary hydroxyl groups and/or lower primary hydroxyl numbersthan the highly reactive polyols. In some embodiments, the less reactivepolyols can have hydroxyl numbers of less than 250, less than 225, lessthan 200, less than 175, less than 150, less than 125, less than 100,less than 80, less than 60, less than 40, or even less than 20. In someembodiments, the less reactive polyols have about 50% or less primaryhydroxyl groups, about 40% or less primary hydroxyl groups, about 30% orless primary hydroxyl groups, about 20% or less primary hydroxyl groups,or even about 10% or less primary hydroxyl groups. In some embodiments,the less reactive polyols can have primary hydroxyl numbers of less thanabout 220, less than about 200, less than about 180, less than about160, less than about 140, less than about 120, less than about 100, lessthan about 80, less than about 60, less than about 40, or even less thanabout 20. Suitable less reactive polyols include castor oil; StepanpolPS-2052A (commercially available from the Stepan Company); Agrol 2.0,3.6, 4.3, 5.6 and 7.0 (plant-based polyols commercially available fromBioBased Technologies); Ecopol 123 and Ecopol 124, which arecommercially available from Ecopur Industries; Honey Bee HB-150 andHB-230, soybean oil-based polyols commercially available from MCPUPolymer Engineering; Terol 1154, commercially available from Oxid(Houston, Tex.); Multranol 3900, Multranol 3901, Arcol 11-34, Arcol24-32, Arcol 31-28, Arcol E-351, Arcol LHT-42, and Arcol LHT-112,commercially available from Bayer; and Voranol 220-028, 220-094,220-110N, 222-056, 232-027, 232-034, and 232-035, commercially availablefrom Dow.

The one or more polyol can include 50% or less of one or more lessreactive polyols in addition to the one or more highly reactive polyols.For example, the one or more polyol can include less than 45%, less than40%, less than 35%, less than 30%, less than 25%, less than 20%, lessthan 15%, less than 10%, or less than 5%, of one or more less reactivepolyols.

The one or more polyol for use in the disclosure can have an averagefunctionality of 1.5 to 8.0, 1.6 to 6.0, 1.8 to 4.0, 2.5 to 3.5, or 2.6to 3.1. The average hydroxyl number values (as measured in units of mgKOH/g) for the one or more polyol can be from about 100 to 600, 150 to550, 200 to 500, 250 to 440, 300 to 415, and 340 to 400.

The polyurethane composites can include more than one type of polyol.The one or more polyols can be combined in various percentages, e.g.,15-40% of a less reactive polyol and 60-85% of a highly reactive polyol.

The polyurethane systems used to form the composite materials describedherein can include one or more additional isocyanate-reactive monomersin addition to the one or more polyol. The one or more additionalisocyanate-reactive monomers can include, for example, amine andoptionally hydroxyl groups.

In some embodiments, the one or more additional isocyanate-reactivemonomers can include a polyamine. The first isocyanate-reactive monomercan comprise a polyamine. Any suitable polyamine can be used. Suitablepolyamines can correspond to the polyols described herein (for example,a polyester polyol or a polyether polyol), with the exception that theterminal hydroxy groups are converted to amino groups, for example byamination or by reacting the hydroxy groups with a diisocyanate andsubsequently hydrolyzing the terminal isocyanate group to an aminogroup. By way of example, the polyamine can be polyether polyamine, suchas polyoxyalkylene diamine or polyoxyalkylene triamine. Polyetherpolyamines are known in the art, and can be prepared by methodsincluding those described in U.S. Pat. No. 3,236,895 to Lee and Winfrey.Exemplary polyoxyalkylene diamines are commercially available, forexample, from Huntsman Corporation under the trade names Jeffamine®D-230, Jeffamine® D-400 and Jeffamine® D-2000. Exemplary polyoxyalkylenetriamines are commercially available, for example, from HuntsmanCorporation under the trade names Jeffamine® T-403, Jeffamine® T-3000,and Jeffamine® T-5000.

In some embodiments, the additional isocyanate-reactive monomer caninclude an alkanolamine. The alkanolamine can be a dialkanolamine, atrialkanolamine, or a combination thereof. Suitable dialkanolaminesinclude dialkanolamines which include two hydroxy-substituted C₁-C₁₂alkyl groups (e.g., two hydroxy-substituted C₁-C₈ alkyl groups, or twohydroxy-substituted C₁-C₆ alkyl groups). The two hydroxy-substitutedalkyl groups can be branched or linear, and can be of identical ordifferent chemical composition. Examples of suitable dialkanolaminesinclude diethanolamine, diisopropanolamine, ethanolisopropanolamine,ethanol-2-hydroxybutylamine, isopropanol-2-hydroxybutylamine,isopropanol-2-hydroxyhexylamine, ethanol-2-hydroxyhexylamine, andcombinations thereof. Suitable trialkanolamines include trialkanolamineswhich include three hydroxy-substituted C₁-C₁₂ alkyl groups (e.g., threehydroxy-substituted C₁-C₈ alkyl groups, or three hydroxy-substitutedC₁-C₆ alkyl groups). The three hydroxy-substituted alkyl groups can bebranched or linear, and can be of identical or different chemicalcomposition. Examples of suitable trialkanolamines includetriisopropanolamine (TIPA), triethanolamine,N,N-bis(2-hydroxyethyl)-N-(2-hydroxypropyl)amine (DEIPA),N,N-bis(2-hydroxypropyl)-N-(hydroxyethyl)amine (EDIPA),tris(2-hydroxybutyl)amine, hydroxyethyl di(hydroxypropyl)amine,hydroxypropyl di(hydroxyethyl)amine, tri(hydroxypropyl)amine,hydroxyethyl di(hydroxy-n-butyl)amine, hydroxybutyldi(hydroxypropyl)amine, and combinations thereof.

In some embodiments, the additional isocyanate-reactive monomer cancomprise an adduct of an alkanolamine described above with an alkyleneoxide. The resulting amine-containing polyols can be referred to asalkylene oxide-capped alkanolamines. Alkylene oxide-capped alkanolaminescan be formed by reacting a suitable alkanolamine with a desired numberof moles of an alkylene oxide. Any suitable alkylene oxide orcombination of alkylene oxides can be used to cap the alkanolamine. Insome embodiments, the alkylene oxide is selected from the groupconsisting of ethylene oxide, propylene oxide, butylene oxide, andcombinations thereof. Alkylene oxide-capped alkanolamines are known inthe art, and include, for example, propylene oxide-cappedtriethanolamine sold under the trade names CARPOL® TEAP-265 and CARPOL®TEAP-335 (Carpenter Co., Richmond, Va.).

In some embodiments, the additional isocyanate-reactive monomer caninclude an alkoxylated polyamine (i.e., alkylene oxide-cappedpolyamines) derived from a polyamine and an alkylene oxide. Alkoxylatedpolyamine can be formed by reacting a suitable polyamine with a desirednumber of moles of an alkylene oxide. Suitable polyamines includemonomeric, oligomeric, and polymeric polyamines. In some cases, thepolyamines has a molecular weight of less than 1000 g/mol (e.g., lessthan 800 g/mol, less than 750 g/mol, less than 500 g/mol, less than 250g/mol, or less than 200 less than 200 g/mol). Examples of suitablepolyamines that can be used to form alkoxylated polyamines includeethylenediamine, 1,3-diaminopropane, putrescine, cadaverine,hexamethylenediamine, 1,2-diaminopropane, o-phenylenediamine,m-phenylenediamine, p-phenylenediamine, spermidine, spermine,norspermidine, toluene diamine, 1,2-propane-diamine, diethylenetriamine,triethylenetetramine, tetraethylene-pentamine (TEPA),pentaethylenehexamine (PEHA), and combinations thereof.

Any suitable alkylene oxide or combination of alkylene oxides can beused to cap the polyamine. In some embodiments, the alkylene oxide isselected from the group consisting of ethylene oxide, propylene oxide,butylene oxide, and combinations thereof. Alkylene oxide-cappedpolyamines are known in the art, and include, for example, propyleneoxide-capped ethylene diamine sold under the trade name CARPOL® EDAP-770(Carpenter Co., Richmond, Va.) and ethylene and propylene oxide-cappedethylene diamine sold under the trade name CARPOL® EDAP-800 (CarpenterCo., Richmond, Va.).

The additional isocyanate-reactive monomer (when used) can be present invarying amounts relative the one or more polyol used to form thepolyurethane. In some embodiments, the additional isocyanate-reactivemonomer can be present in an amount of 30% or less, 25% or less, 20% orless, 15% or less, 10% or less, or 5% or less by weight based on theweight of the one or more polyol.

As indicated herein, in the polyurethane composites, an isocyanate isreacted with a polyol (and any additional isocyanate-reactive monomers)to produce the polyurethane formulation. In general, the ratio ofisocyanate groups to the total isocyanate reactive groups, such ashydroxyl groups, water and amine groups, is in the range of about 0.5:1to about 1.5:1, which when multiplied by 100 produces an isocyanateindex between 50 and 150. Additionally, the isocyanate index can be fromabout 80 to about 120, from about 90 to about 120, from about 100 toabout 115, or from about 105 to about 110. As used herein, an isocyanatemay be selected to provide a reduced isocyanate index, which can bereduced without compromising the chemical or mechanical properties ofthe composite material.

One or more catalysts can be added to facilitate curing and can be usedto control the curing time of the polymer matrix. Examples of usefulcatalysts include amine-containing catalysts (such as DABCO,tetramethylbutanediamine, and diethanolamine) and tin-, mercury-, andbismuth-containing catalysts. In some embodiments, 0.01 wt % to 2 wt %catalyst or catalyst system (e.g., 0.025 wt % to 1 wt %, 0.05 wt % to0.5 wt %, or 0.1 wt % to about 0.25 wt %) can be used based on theweight of the polyurethane composite.

The polyurethane can be present in the composite in amounts from 10% to60% based on the weight of polyurethane composite. For example, thepolyurethane can be included in an amount from 15% to 60% or 20% to 50%by weight, based on the weight of the polyurethane composite. In someembodiments, the polyurethane in the polyurethane composites can bepresent in an amount of 10% or greater, 15% or greater, 20% or greater,25% or greater, 30% or greater, 35% or greater, 40% or greater, 45% orgreater, 50% or greater, or 55% or greater by weight, based on theweight of polyurethane composite. In some embodiments, the polyurethanein the polyurethane composites can be present in an amount of 60% orless, 55% or less, 50% or less, 45% or less, 40% or less, 35% or less,30% or less, 25% or less, 20% or less, or 15% or less by weight, basedon the weight of polymeric composite.

The polyurethane composites can include a particulate filler. In someexamples, the particulate filler includes fly ash. Fly ash is producedfrom the combustion of pulverized coal in electrical power generatingplants. The fly ash useful with the composite materials described hereincan be Class C fly ash, Class F fly ash, or a mixture thereof. Fly ashproduced by coal-fueled power plants is suitable for incorporation inthe composites described herein.

In some embodiments, the particle size distribution of the fly ash caninclude 50% or greater of fly ash particles by weight having a diameterof from 0.2 micron to 100 microns. For example, 55% or greater, 60% orgreater, 65% or greater, 70% or greater, 75% or greater, 80% or greater,85% or greater, or 90% or greater of the fly ash particles by weight canhave a diameter of from 0.2 micron to 100 microns. In some embodiments,50% or greater of the fly ash can have a particle diameter of 100microns or less, 95 microns or less, 90 microns or less, 85 microns orless, 80 microns or less, 75 microns or less, 70 microns or less, 65microns or less, 60 microns or less, 55 microns or less, 50 microns orless, and can have a particle diameter of 0.2 microns or more, 0.3microns or more, 0.4 microns or more, 0.5 microns or more, 0.7 micronsor more, 1 micron or more, 2 microns or more, 5 microns or more, or 10microns or more. In some examples, the 50% or greater of the fly ash canhave a particle diameter of from 0.2 microns to 100 microns, 0.2 micronsto 90 microns, or 0.3 microns to 80 microns, 1 to 60 microns, or 5 to 50microns.

In some embodiments, the fly ash can have a particle size distributionwith at least three modes. For example, the particle size distributionof the fly ash can be three, four, five, or more modes. Alternatively,the fly ash can be blended with another fly ash to modify the propertiesof the fly ash to produce a fly ash having a particle size distributionwith at least three modes.

The fly ash particle size distribution can include a first mode having amedian particle diameter of 2.0 microns or less. In some examples, themedian particle size of the first mode can be 0.3 microns to 1.5microns, 0.4 microns to 1 microns, or 0.5 microns to 0.8 microns (e.g.,0.7 microns). The fly ash particle size distribution can include asecond mode having a median particle diameter of from 3 microns to lessthan 40 microns. In some examples, the median particle size of thesecond mode can be from 5 microns to 35 microns, 10 microns to 30microns, or 10 microns to 25 microns. The fly ash particle sizedistribution can include a third mode having a median particle diameterof 40 microns or greater. In some examples, the median particle size ofthe third mode can be from 40 microns to less than 100 microns, forexample from 40 microns to 90 microns, 40 microns to 80 microns, or from40 microns to 75 microns. In some embodiments, the fly ash particle sizedistribution can include a first mode having a median particle diameterof from 0.3 microns to 1.0 micron, a second mode having a medianparticle diameter of from 10 microns to 25 microns, and a third modehaving a median particle diameter of from 40 microns to 80 microns. Insome examples, the fly ash can also include an additional ultrafine modewith a median particle diameter of from 0.05 microns to 0.2 microns.

In some embodiments, the particle size distribution can include 11-17%of the particles by volume in the first mode, 56-74% of the particles byvolume in the second mode, and 12-31% of the particles by volume in thethird mode. The ratio of the volume of particles in the second and thirdmodes to the volume of particles in the first mode can be from 4.5 to7.5.

The fly ash can be present in the polyurethane composites in amountsfrom 20% to 90% by weight. In some embodiments, the fly ash can bepresent in amounts from 35% to 80% such as from 50% to 80% or from 50%to 75% by weight. Examples of the amount of fly ash present in thecomposites described herein include 20%, 25%, 30%, 31%, 32%, 33%, 34%,35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%,49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%,63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%,77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, or 90%by weight.

The particulate filler can include an additional filler material. Theadditional filler material can include a coarse filler material or acombination of coarse filler materials. The coarse filler material canbe any natural or synthetic material, based on inorganic materials,organic materials, or combinations of both. In some embodiments, thecoarse filler material can include silica sand, silica fume, cement,slag, metakaolin, talc, mica, wollastonite, limestone, calciumcarbonate, perlite, clay (e.g., kaolin), shale, ceramic, glass, seedhull, organic waste, or combinations thereof. In some embodiments, thecoarse filler can include an organic material, such as a recycledpolymeric material. Suitable examples include pulverized polymeric foamor recycled rubber material. In some examples, the coarse fillermaterial can include expanded glass. In other examples, the coarsefiller material can include sand. In some embodiments, the coarse filleris not fly ash.

In some embodiments, 80% or greater of the coarse filler particles byweight have a particle diameter of from greater than 250 microns to 10mm, greater than 250 microns to 5 mm, greater than 250 microns to 2 mm,greater than 250 microns to 1 mm, or 250 microns to 500 microns. Forexample, the coarse filler material can include 85% or greater, 90% orgreater, or 95% or greater of filler particles by weight having aparticle diameter of from 250 microns to 10 mm, 250 microns to 5 mm, 250microns to 2 mm, 250 microns to 1 mm, or 250 microns to 500 microns. Insome embodiments, 80% or greater of the coarse filler particles have aparticle diameter of 250 microns or greater, 300 microns or greater, or350 microns or greater, and a particle diameter of 10 mm or less, 8 mmor less, 5 mm or less, 4 mm or less, 3 mm or less, 2 mm or less, 1 mm orless, or 500 microns or less.

In some embodiments, the particle size distribution of the coarse fillermaterial can include having a diameter of from 250 microns to 10 mm.

The coarse filler material can be present in the polyurethane compositein any suitable amount to confer a desirable property to thepolyurethane composite. The coarse filler material can be present in thepolyurethane composite in amounts from 0.1% to 50% by weight, based onthe total weight of the composite. For example, the coarse fillermaterial can be in amounts of from 1% to 40%, 1% to 30%, 1% to 20%, or1% to 10% by weight, based on the total weight of the composite. In someembodiments, the coarse filler material can be present in thepolyurethane composite in amounts of 0.1% or greater, 0.5% or greater,1% or greater, 1.25% or greater, 1.5% or greater, 2% or greater, 3% orgreater, 4% or greater, or 5% or greater by weight, based on the totalweight of the composite. In some embodiments, the coarse filler materialcan be present in the polyurethane composite in amounts of 50% or less,40% or less, 30% or less, 20% or less, 15% or less, 10% or less, 8% orless, or 5% or less by weight, based on the total weight of thecomposite.

The weight ratio of the fly ash to the coarse filler material can be 1:1or greater. For example, the weight ratio of the fly ash to the coarsefiller material can be from 1:1 to 200:1, 5:1 to 200:1, 9:1 to 200:1,9:1 to 150:1, 9:1 to 100:1, 9:1 to 80:1, or 9:1 to 50:1. In someembodiments, the weight ratio of the fly ash to the coarse fillermaterial can be 2:1 or greater, 5:1 or greater, 9:1 or greater, 10:1 orgreater, 20:1 or greater, 30:1 or greater, 40:1 or greater, 50:1 orgreater, 60:1 or greater, or 70:1 or greater. In some embodiments, theweight ratio of the fly ash to the coarse filler material can be 200:1or less, 175:1 or less, 150:1 or less, 125:1 or less, 100:1 or less,75:1 or less, or 50:1 or less.

In some embodiments, a fiber material can be included in thepolyurethane composite, e.g., to provide increased strength, stiffnessor toughness. The fiber material can be any natural or synthetic fibermaterial, based on inorganic materials, organic materials, orcombinations of both. Fiber materials suitable for use with thepolyurethane composite described herein can be present in the form ofindividual fibers, fabrics, rovings, or tows. Exemplary fiber materialsthat can be used in the polyurethane composite include mineral woolfibers such as stone wool, slag wool, or ceramic fiber wool. The mineralwool fibers can be synthetic or can be obtained from molten mineral suchas lava, rock or stone. Other suitable inorganic fiber materials includebasalt fibers, alumina silica fibers, aluminum oxide fibers, silicafibers, carbon fibers, metal fibers, and combinations thereof. Exemplaryorganic fiber materials that can be used in the polyurethane compositeinclude hemp fibers, sisal fibers, cotton fibers, straw, reeds, or othergrasses, jute, bagasse fibers, abaca fibers, flax, southern pine fibers,wood fibers, cellulose, saw dust, wood shavings, lint, vicose, leatherfibers, rayon, and mixtures thereof. Other suitable organic fibermaterials include synthetic fibers such as, Kevlar, viscose fibers,polyamide fibers, polyacrylonitrile fibers, Dralon® fibers, polyethylenefibers, polypropylene fibers, polyvinyl alcohol fibers, polyacrylicfibers, polyester fibers, aramid fibers, carbon fibers, or combinationsthereof. In some embodiments, the polyurethane composites can include acombination of fibers that break and fibers that do not break when thecomposite is fractured by external stress.

The fiber material (when used) can be present in the polyurethanecomposites in amounts from 0.5% to 20% by weight, based on the weight ofpolyurethane composite. For example, the fiber material can be presentin amounts from 1% to 20%, 1% to 10%, 1.5% to 8%, 2% to 6%, or 2% to 4%by weight, based on the weight of the polyurethane composite.

In some embodiments, the polyurethane composites can comprise aplurality of glass fibers as the fiber material. Glass fibers caninclude fibrous glass such as E-glass, C-glass, S-glass, and AR-glassfibers. In some examples, fire resistant or retardant glass fibers canbe included to impart fire resistance or retarding properties to thepolyurethane composites. The glass fibers can be from 1 mm to 50 mm inaverage length. In some examples, the glass fibers are from 1.5 mm to 30mm, from 2 mm to 30 mm, from 3 mm to 30 mm, or from 3 mm to 15 mm inaverage length. In some examples, the average length of the glass fibersin the polyurethane composites can be 1 mm or greater, 1.5 mm orgreater, 2 mm or greater, 3 mm or greater, 4 mm or greater, 5 mm orgreater, or 6 mm or greater. In some embodiments, the average length ofthe glass fibers can be 50 mm or less, 40 mm or less, 30 mm or less, 20mm or less, 15 mm or less, 12 mm or less, or 10 mm or less. The glassfibers in the polyurethane composites can have any dimension of from 1μm to 30 μm in average diameter. For example, the average diameter ofthe glass fibers can be 1.5 μm to 30 μm, 3 μm to 20 μm, 4 μm to 18 μm,or 5 μm to 15 μm in average diameter. The glass fibers can be providedin a random orientation or can be axially oriented.

In some embodiments, the fibers, coarse filler material, and/or the flyash can be coated with a composition to modify their reactivity. Forexample, the fibers, coarse filler material, and/or the fly ash can becoated with a sizing agent. In some embodiments, the fibers, coarsefiller material, and/or the fly ash can be coated with a composition forpromoting adhesion. U.S. Pat. No. 5,064,876 to Hamada et al. and U.S.Pat. No. 5,082,738 to Swofford, for example, disclose compositions forpromoting adhesion. In some embodiments, the fibers, coarse fillermaterial, and/or the fly ash are surface coated with a compositioncomprising a silane compound such as aminosilane. U.S. Pat. No.4,062,999 to Kondo et al. and U.S. Pat. No. 6,602,379 to Li et al.describe suitable aminosilane compounds for coating fibers. In someembodiments, the polyurethane composites can include a combination ofcoated and uncoated fibers, coarse filler material, and/or the fly ash.In some examples, the coarse filler material can be coated with anaminosilane.

Additional components useful with the polyurethane composite can includefoaming agents, blowing agents, surfactants, chain-extenders,crosslinkers, coupling agents, UV stabilizers, fire retardants,antimicrobials, anti-oxidants, and pigments. For example, the fibers,coarse filler material, and/or the fly ash can be coated with asurfactant, bonding agent, pigment, or combinations thereof. Though theuse of such components is well known to those of skill in the art, someof these additional additives are further described herein.

Chemical foaming agents include azodicarbonamides (e.g., Celogenmanufactured by Lion Copolymer Geismar); and other materials that reactat the reaction temperature to form gases such as carbon dioxide. Wateris an exemplary foaming agent that reacts with isocyanate to yieldcarbon dioxide. The presence of water as an added component or in thefiller also can result in the formation of polyurea bonds through thereaction of the water and isocyanate. In some embodiments, water may bepresent in the mixture used to produce the polyurethane composite in anamount of from greater than 0% to 5% by weight or less, based on theweight of the mixture. In some embodiments, water can be present in arange of 0.02% to 4%, 0.05% to 3%, 0.1% to 2%, or 0.2% to 1% by weight,based on the weight of the mixture. In some embodiments, the mixtureused to produce the polyurethane composite includes less than 0.5% byweight water.

Surfactants can be used as wetting agents and to assist in mixing anddispersing the materials in a composite. Surfactants can also stabilizeand control the size of bubbles formed during the foaming event and theresultant cell structure. Surfactants can be used, for example, inamounts below about 0.5 wt % based on the total weight of the mixture.Examples of surfactants useful with the polyurethanes described hereininclude anionic, non-ionic and cationic surfactants. For example,silicone surfactants such as Tegostab B-8870, DC-197 and DC-193 (AirProducts; Allentown, Pa.) can be used.

Low molecular weight reactants such as chain-extenders and/orcrosslinkers can be included in the composite described herein. Thesereactants help the polyurethane system to distribute and contain the flyash, coarse filler material, and/or fibers within the composite.Chain-extenders are difunctional molecules, such as diols or diamines,that can polymerize to lengthen the urethane polymer chains. Examples ofchain-extenders include ethylene glycol; 1,4-butanediol; ethylenediamine, 4,4′-methylenebis(2-chloroaniline) (MBOCA); diethyltoluenediamine (DETDA); and aromatic diamines such as Unilink 4200(commercially available from UOP). Crosslinkers are tri- or greaterfunctional molecules that can integrate into a polymer chain through twofunctionalities and provide one or more further functionalities (i.e.,linkage sites) to crosslink to additional polymer chains. Examples ofcrosslinkers include glycerin, trimethylolpropane, sorbitol,diethanolamine, and triethanolamine. In some composites, a crosslinkeror chain-extender may be used to replace at least a portion of the oneor more polyol in the composite material. For example, the polyurethanecan be formed by the reaction of an isocyanate, a polyol, and acrosslinker.

Coupling agents and other surface treatments such as viscosity reducers,flow control agents, or dispersing agents can be added directly to thefiller or fiber, or incorporated prior to, during, and/or after themixing and reaction of the composite material. Coupling agents can allowhigher filler loadings of the particulate filler such as fly ash and/orthe coarse filler material and may be used in small quantities. Forexample, the composite material may comprise about 0.01 wt % to about0.5 wt % of a coupling agent. Examples of coupling agents useful withthe composite materials described herein include Ken-React LICA 38 andKEN-React KR 55 (Kenrich Petrochemicals; Bayonne, N.J.). Examples ofdispersing agents useful with the composite materials described hereininclude JEFFSPERSE X3202, JEFFSPERSE X3202RF, and JEFFSPERSE X3204(Huntsman Polyurethanes; Geismar, La.).

Ultraviolet light stabilizers, such as UV absorbers, can be added to thecomposite materials described herein. Examples of UV light stabilizersinclude hindered amine type stabilizers and opaque pigments like carbonblack powder. Fire retardants can be included to increase the flame orfire resistance of the composite material. Antimicrobials can be used tolimit the growth of mildew and other organisms on the surface of thecomposite. Antioxidants, such as phenolic antioxidants, can also beadded. Antioxidants provide increased UV protection, as well as thermaloxidation protection.

Pigments or dyes can optionally be added to the composite materialsdescribed herein. An example of a pigment is iron oxide, which can beadded in amounts ranging from about 2 wt % to about 7 wt %, based on thetotal weight of the composite material.

Methods of preparing the polyurethane composites are described herein.The polyurethane composites can be formed by the reaction of one or moreisocyanate, selected from the group consisting of diisocyanates,polyisocyanates, and mixtures thereof, and one or more polyol, in thepresence of a coarse filler material, fly ash, and optionally, a fibermaterial and/or a catalyst. In some embodiments, the polyurethanecomposite can be produced by mixing the one or more isocyanates, the oneor more polyols, the coarse filler material, and the fly ash, in amixing apparatus such as a high speed mixer or an extruder. In someembodiments, mixing can be conducted in an extruder. The materials canbe added in any suitable order. For example, in some embodiments, themixing stage of the method used to prepare the polyurethane compositecan include: (1) mixing the polyol, coarse filler material, and fly ash;(2) mixing the isocyanate with the polyol, coarse filler material, andfly ash; and optionally (3) mixing the catalyst with the isocyanate, thepolyol, the coarse filler material, and the fly ash. The optional fibermaterial can be added at the same time as the coarse filler material orfly ash, or can be added prior to, during, or after stage (2) or (3).

The polyurethane composite mixture can be blended in any suitable mannerto obtain a homogeneous or heterogeneous blend of the one or moreisocyanate, one or more polyol, fly ash, coarse filler material,optional fiber, and optional catalyst. An ultrasonic device can be usedfor enhanced mixing and/or wetting of the various components of thecomposite. The ultrasonic device produces an ultrasound of a certainfrequency that can be varied during the mixing and/or extrusion process.The ultrasonic device useful in the preparation of composite materialsdescribed herein can be attached to or adjacent to an extruder and/ormixer. For example, the ultrasonic device can be attached to a die ornozzle or to the port of an extruder or mixer. An ultrasonic device mayprovide de-aeration of undesired gas bubbles and better mixing for theother components, such as blowing agents, surfactants, and catalysts.

The mixture can then be extruded into a mold cavity of a mold, the moldcavity formed by at least an interior mold surface. The mold can be acontinuous forming system such as a belt molding system or can includeindividual batch molds. The belt molding system can include a moldcavity formed at least in part by opposing surfaces of two opposedbelts. A molded article can then be formed followed by removal of thearticle from the mold.

Incorporation of the coarse filler material into the filled polyurethanemixture (that is, the polyol, isocyanate, coarse filler material, andfly ash) can decrease the viscosity of the mixture. In some embodiments,it is desirable that the composite mixture has a viscosity below aparticular threshold at the desired loadings so it can be effectivelyprocessed. In some embodiments, the coarse filler material can bepresent in the composite mixture in amounts to produce a workableviscosity of from 25 Pa·s to 250 Pa·s. For example, the coarse fillermaterial in the composite mixture can be in amounts to produce aworkable viscosity from 30 Pa·s to 250 Pa·s, 65 Pa·s to 250 Pa·s, or 80Pa·s to 250 Pa·s. In some embodiments, the working viscosity can be lessthan 250 Pa·s, less than 225 Pa·s, less than 200 Pa·s, less than 175Pa·s, less than 150 Pa·s, less than 140 Pa·s, less than 130 Pa·s, lessthan 120 Pa·s, or less than 110 Pa·s. The polyurethane mixture may beprocessed at an elevated temperature (e.g., 200-500° F.) to form a meltand to allow the mixture to have a workable viscosity. In someembodiments, the fly ash and/or the coarse filler material are heatedbefore mixing with the polyurethane. The viscosity of the compositemixture can be measured using a Thermo Electron Corporation HaakeViscometer.

In some embodiments, the composite mixture described herein can befoamed. The polyol and the isocyanate can be allowed to produce a foamedcomposite material after mixing the components according to the methodsdescribed herein. The composite materials can be formed while they areactively foaming or after they have foamed. For example, the materialcan be placed under the pressure of a mold cavity prior to or during thefoaming of the composite material.

Incorporation of the coarse filler material in the polyurethanecomposite can increase the flexural strength of a composite, compared toa composite without the coarse filler material. In some embodiments, theflexural strength of the polyurethane composites can be increased by atleast 10%, for example, 15% or greater, 20% or greater, 25% or greater,30% or greater, 35% or greater, 50% or greater, 75% or greater, or even100% or greater, compared to a composite without coarse fillermaterials.

The flexural strength of the polyurethane composites described hereincan be 300 psi or greater. For example, the flexural strength of thepolyurethane composites can be 500 psi or greater, 700 psi or greater,900 psi or greater, 1000 psi or greater, 1100 psi or greater, 1200 psior greater, 1300 psi or greater, 1400 psi or greater, 1500 psi orgreater, or 1600 psi or greater. The flexural strength can be determinedby the load required to fracture a rectangular prism loaded in the threepoint bend test as described in ASTM C1185-08 (2012).

Incorporation of the coarse filler material in the polyurethanecomposite can increase the packing density of the fillers in thecomposite, compared to a composite without the coarse filler material.In some embodiments, the packing density of the fillers in thepolyurethane composites can be increased by at least 0.5%, for example,0.7% or greater, 1% or greater, 1.5% or greater, 2% or greater, 3% orgreater, 5% or greater, or 8% or greater, compared to the packingdensity of fillers in a composite without coarse filler materials. Thepacking density of the fillers in the polyurethane composites describedherein can be 1.1 g/ml or greater. For example, the packing density ofthe polyurethane composites can be 1.2 g/ml or greater, or 1.3 g/ml orgreater. The packing density can be determined by packing the compositematerials into a graduated cylinder held onto a table vibrated by aSyntron magnetic vibrator for several minutes until the material nolonger reduces in volume, then calculating the density. The method ismodified based on tapped density obtained using ASTM D7481-09.

The granulometry of the coarse filler material and/or fly ash can bedetermined by a variety of techniques. For example, analysis of theparticle size distribution of the fly ash or coarse filler material canbe conducted using a Horiba LA-300 laser interferometer with isopropanoldispersion media. The multimodal distribution can be analyzed into itscomponent parts by mathematical deconvolution using a computer programsuch as MATLAB® from Mathworks.

The optimization of various properties, such as density and flexuralstrength, of the composite allows their use in building materials andother structural applications. For example, the polyurethane compositescan be formed into shaped articles and used in building materialsinclude siding materials, roofing materials such as roof coatings androof tiles, architectural moldings, sheets, decking materials, syntheticlumber, sound barrier/insulation, thermal barriers, carpet backing,fencing materials, marine lumber, flexible or rigid foams such asautomotive foams (e.g., for dashboard, seats or roofing), componentcoatings, and other shaped articles. Examples of shaped articles madeusing composite materials described herein include roof tile shingles,trim boards, building panels, scaffolding, cast molded products, doors,door parts, moldings, sills, stone, masonry, brick products, posts,signs, guard rails, retaining walls, park benches, tables, slats, cornerarches, columns, wall boards, ceiling tiles, ceiling boards, soffits,and railroad ties. The polyurethane composites described herein furthercan be used as reinforcement of composite structural members includingbuilding materials such as doors, windows, furniture, and cabinets andfor well and concrete repair. The polyurethane composites describedherein also can be used to fill gaps, particularly to increase thestrength of solid surface articles and/or structural components. Thepolyurethane composites can be flexible, semi-rigid or rigid foams. Insome embodiments, the flexible foam is reversibly deformable (i.e.resilient) and can include open cells. An 8″×1″×1″ piece of a flexiblefoam can generally wrap around a 1″ diameter mandrel at room temperaturewithout rupture or fracture. Flexible foams also generally have adensity of less than 5 lb/ft³ (e.g. 1 to 5 lb/ft³). In some embodiments,the rigid foam is irreversibly deformable and can be highly crosslinkedand/or can include closed cells. Rigid foams generally have a density of5 lb/ft³ or greater.

In some embodiments, the overall density of the polyurethane compositesand/or the molded articles described herein can be 2 lb/ft³ or greater.For example, the overall density can be 5 lb/ft³ to 75 lb/ft³, 10 lb/ft³to 70 lb/ft³, 15 lb/ft³ to 65 lb/ft³, 20 lb/ft³ to 60 lb/ft³, 25 lb/ft³to 55 lb/ft³, or 10 lb/ft³ to 35 lb/ft³.

EXAMPLES

The following examples are put forth so as to provide those of ordinaryskill in the art with a complete disclosure and description of how thecompounds, compositions, articles, devices and/or methods claimed hereinare made and evaluated, and are intended to be purely exemplary and arenot intended to limit the scope of the disclosure. Unless indicatedotherwise, parts are parts by weight, temperature is in ° C. or is atambient temperature, and pressure is at or near atmospheric.

Effect of Blast Sand or Geotex Filler Materials on Packing Density

The packing density of mixtures of fly ash and blast sand of Geotexfiller was determined by fly ash and filler material (in amountsdisclosed in FIG. 1) into a graduated cylinder held onto a tablevibrated by a Syntron magnetic vibrator for several minutes until thematerial no longer reduces in volume, then the density was calculated.

Results:

FIG. 1 shows the vibrated density of a blend of fly ash and coarsefiller materials (blast sand from Keller Materials, TX and Geotex 30-50,a marble limestone/calcium carbonate filler supplied by Huber EngineeredMaterials, IL) with various percentages of the coarse filler in theblend. The blast sand has an equivalent particle size diameter rangefrom 100 micrometer to 300 micrometer. The Geotex 30-50 has anequivalent particle size diameter range from 200 micrometer to 500micrometer. Vibrated (compacted) density is measured by packing fillermaterials into a graduated cylinder held onto a table vibrated by aSyntron magnetic vibrator for several minutes until the filler materialsno longer reduce in volume, then calculating the density. Asdemonstrated, the addition of coarse filler materials increases thepacking density and reduces the porosity in the composite system, thusrequiring less polyurethane to fill the pores and allowing morepolyurethane available to wet the particles.

Effect of Blast Sand or Geotex Filler Materials on the Viscosity ofPolyurethane Composites

Method:

Polyol compositions used to simulate highly filled polyurethane systemswere prepared by mixing a polyol blend containing 30% by weight CARPOL®MX-425 (Mannich base polyether polyol), 19.7% by weight CARPOL® GP-725(alkylene oxide-capped glycerine), 19.3% by weight CARPOL® GSP-355(sucrose-based polyether polyol), 19% by weight TEROL® 352 (aromaticpolyester polyol), and 10% by weight EDAP-800 (ethylene diamine,propylene oxide and ethylene oxide based polyether polyol) to produce apolyol mixture. Fly ash and blast sand or Geotex filler materials (inthe amounts disclosed in FIG. 2), were added and wetted with the liquidsolution. The viscosity of the filler/polyol mixture was thendetermined.

Results:

FIG. 2 shows the viscosity of the filler-polyurethane system decreasessignificantly with addition of the filler material(s), even to almostone order of magnitude in some cases. For example, the viscosity of a75% fly ash/25% polyol blend has a viscosity of about 140,000 cP, whilethat of a 52.5% fly ash/22.5% blast sand/25% polyol has a viscosity ofonly about 30,000. Therefore, by utilization of a coarse filler materialor a mixture of coarse filler materials, the workability of the startingmixture of a highly-filled polyurethane composite material can bedramatically improved, thus making the manufacturing process of suchmaterials much easier.

Effect of Blast Sand or Poraver Filler Materials on PolyurethaneComposite

Methods:

Polyurethane composites were prepared using blast sand, obtained fromKeller Materials, TX, USA, or Poraver, obtained from North America Inc,Innisfil, Ontario. The Poraver materials are a family of lightweightexpanded glass/clay materials. The composites were prepared by mixing apolyol blend containing 30% by weight CARPOL® MX-425 (Mannich basepolyether polyol), 19.7% by weight CARPOL® GP-725 (alkylene oxide-cappedglycerine), 19.3% by weight CARPOL® GSP-355 (sucrose-based polyetherpolyol), 19% by weight TEROL® 352 (aromatic polyester polyol), and 10%by weight EDAP-800 (ethylene diamine, propylene oxide and ethylene oxidebased polyether polyol) to produce a polyol mixture. The polyol mixturewas then mixed with 1% by weight of an amine catalyst (diethanolamine),and 2% by weight of a silicone surfactant (Tegostab B-8870) in anextruder. Fly ash, glass fiber, and blast sand or Poraver were added andwetted with the liquid solution. Methylene diphenyl diisocyanate (MDI;104 index; 51.5 g) was then added to the extruder, and simultaneouslystirring began. The mixture was extruded into a belt molding system andallowed to cure. The resultant composites included 23 parts by weightpolyurethane, 70 parts by weight fly ash, 7 parts by weight glass fiber,and the weight percentage of blast sand or Poraver provided in Tables 1and 2. The physical properties of the resultant composites, includingflexural strength and density were determined.

TABLE 1 The flexural strength and density of highly-filled polyurethanewith various addition levels of blast sand. Addition Flexural Level,Strength, Density, wt % psi pcf 0 1066 32.7 10 1076 36.3 15 1142 38.4 201406 37.1 25 1209 40.8 30 1344 41.1

TABLE 2 The flexural strength and density of highly-filled polyurethanewith various addition levels of Poraver filler (0.5-1 mm, 0.2-0.5 mm and0.1-0.3 mm). 0.5-1 mm 0.2-0.5 mm 0.1-0.3 mm Addition Flexural AdditionFlexural Addition Flexural Level, Strength, Density, Level, Strength,Density, Level, Strength, Density, wt % psi pcf wt % psi pcf wt % psipcf 1 1117 35.3 1 1073 35.1 1 1117 35.0 2 1194 36.5 2 1206 35.4 2 116736.2 3 1089 35.5 3 1356 36.3 3 1295 36.4 4 1477 37.2 4 1233 37.0 4 104736.4 5 1577 37.6 5 1337 37.2 5 1269 37.5 6 1580 37.8 6 1472 38.0 6 123636.9

Results:

Tables 1 and 2 describe the flexural strength and density of highlyfilled polyurethane composite materials with different levels ofaddition of blast sand and Poraver materials, respectively. A flexuralstrength of about 1400 psi was achieved with 20% by weight addition ofblast sand at a density of 37.1 pcf, 4% by weight addition of Poraver0.5-1 mm at a density of 37.2 pcf and 6% by weight addition of Poraver0.2-0.5 mm at a density of 38 pcf, compared to about 1000 psi at similardensity level for the control formulation (FIG. 3). In FIG. 3, FA is flyash; PUR is polyurethane from polyol and methyl diisocyanate; and FG ischopped fiber glass.

Summary:

In addition to the advantage in processing of the starting mixture ofthe final composite, the use of coarse filler materials in highly-filledpolyurethane composite also improves the mechanical properties such asflexural strength while permitting a reduction in cost of the composite.The addition of the coarse filler material also improves the packing offiller particles in the filler-fiber-polyurethane system and makes thestructure denser and stronger. Because the total porosity is reduced,less polyurethane is required to form an optimal structure forsatisfactory performance and thus reduces the cost of the compositeproducts without compromising the mechanical properties. The reducedporosity allows for a greater amount of the polyol and MDI mixtureavailable to coat particles and form the struts of the composite.

Effect of Glass Fibers on Blast Sand or Poraver Filled PolyurethaneComposite

Methods:

Polyurethane composites were prepared by mixing a polyol blendcontaining 30% by weight CARPOL® MX-425 (Mannich base polyether polyol),19.7% by weight CARPOL® GP-725 (alkylene oxide-capped glycerine), 19.3%by weight CARPOL® GSP-355 (sucrose-based polyether polyol), 19% byweight TEROL® 352 (aromatic polyester polyol), and 10% by weightEDAP-800 (ethylene diamine, propylene oxide and ethylene oxide basedpolyether polyol) to produce a polyol mixture. The polyol mixture wasthen mixed with 1% by weight of an amine catalyst (diethanolamine), and2% by weight of a silicone surfactant (Tegostab B-8870) in an extruder.Fly ash, a coarse filler, and glass fibers (in the amounts disclosed inTable 3), were added and wetted with the liquid solution. Methylenediphenyl diisocyanate (MDI; 104 index; 51.5 g) was then added to theextruder, and simultaneously stirring began. The following mixtures wereprepared: (1) fly ash only (23 wt % polyurethane and 77 wt % of fillersand glass fiber) as provided in the first column of Table 3; (2) a blendof fly ash and blast sand with a weight ratio of 5:1 (20 wt %polyurethane and 80 wt % of fillers and glass fiber) as provided in thesecond column of Table 3; and (3) a blend of fly ash and Poraver 0.5-1mm with a weight ratio of 25:1 (22.4% polyurethane and 77.6% wt % offillers and glass fiber) as provided in the third column of Table 3.

The mixtures were extruded into a belt molding system and allowed tocure. The physical properties of the composites, including flexuralstrength and density were determined.

TABLE 3 The flexural strength and density of highly-filled polyurethanewith various levels of glass fibers. Fly Ash Fly Ash + Blast Sand FlyAsh + Poraver 0.5-1 mm Fiber Flexural Fiber Flexural Fibsr FlexuralGlass, Density, Strength, Glass, Density, Strength, Glass, Density,Strength, wt % pcf psi wt % pcf psi wt % pcf psi 0 28.2 121 0 28.3 132 236.1 176 2 28.6 405 2 27.6 302 4 37.0 255 4 29.8 517 3 34.0 713 6 37.4360 6 29.7 551 5 36.5 886 8 38.2 1361 8 32.9 798 7 37.6 1081 10 32.01232 10 32.7 614 9 38.5 1427 12 33.5 1548 12 35.2 822 11 38.7 1530 1433.6 1338 14 35.4 880 12 38.7 1374

Results:

Table 3 lists the flexural strength and density of highly-filledpolyurethane with various levels of glass fibers. It is shown that, theflexural strength of the composite with either blast sand or Poraver0.5-1 mm increases to above 1500 psi when fiber glass contentsincreases, while that of the control formulation levels off at about 880psi (See FIG. 4). The comparison of the control formulation without anycoarse fillers and the formulations with secondary coarse fillersdemonstrate the advantage of the improvement of the packing of thefiller particles.

As shown in FIG. 3, the flexural strength of the inorganic-organicmaterial with a composition of 73 wt % fly ash, 23% polyurethane and 4%fiber glass increases from about 800 psi at a density of 35 pcf to about1250 psi at a density of 40 pcf and about 2000 psi at a density of 45pcf. Although the mechanical performance can be enhanced by increasingthe density, the cost can be higher if the composition of thefiller-polyurethane is kept constant. Similarly, improvements in themechanical performance of highly-filled polyurethane composites can beobtained by increasing the polyurethane content in the material.However, there is only a limited enhancement in flexural strength withthis method. As shown in Table 4, the flexural strength only increasesabout 15% when the polyurethane content increases from 23% to 41%. Thereis improved handleability and extension with increases in thepolyurethane component of the mixture. However, polyurethane is the mostexpensive ingredient in the composition, so the method of increasingpolyurethane content is not an economical way to improve the mechanicalperformance of highly-filled polyurethane.

TABLE 4 The mechanical properties vs various polyurethane content (PUR:polyurethane). PUR Flexural Content, Strength, Density, Handleability,Extension, Modulus, wt % psi pcf in-lbf/in in ksi 23 2058 45.3 9.8 0.060171 26 2258 44.1 13.7 0.062 209 29 1987 43.8 11.9 0.061 187 32 2382 43.516.8 0.072 193 35 2134 41.7 14.7 0.071 177 38 2091 41.4 16.7 0.082 14941 2265 41.4 19.8 0.090 149

Conclusion:

The partial volumetric replacement of fly ash by a coarse fillermaterial or a combination of coarse filler materials increased thepacking density of the filler particles in highly-filled polyurethanesystem and reduce the viscosity of the material, leading to improvementsin the workability and mechanical performance of the polyurethanecomposites.

The compositions and methods of the appended claims are not limited inscope by the specific compositions and methods described herein, whichare intended as illustrations of a few aspects of the claims and anycompositions and methods that are functionally equivalent are intendedto fall within the scope of the claims. Various modifications of thecompositions and methods in addition to those shown and described hereinare intended to fall within the scope of the appended claims. Further,while only certain representative materials and method steps disclosedherein are specifically described, other combinations of the materialsand method steps also are intended to fall within the scope of theappended claims, even if not specifically recited. Thus, a combinationof steps, elements, components, or constituents may be explicitlymentioned herein; however, other combinations of steps, elements,components, and constituents are included, even though not explicitlystated. The term “comprising” and variations thereof as used herein isused synonymously with the term “including” and variations thereof andare open, non-limiting terms. Although the terms “comprising” and“including” have been used herein to describe various embodiments, theterms “consisting essentially of” and “consisting of” can be used inplace of “comprising” and “including” to provide for more specificembodiments and are also disclosed. As used in this disclosure and inthe appended claims, the singular forms “a”, “an”, “the”, include pluralreferents unless the context clearly dictates otherwise.

1. A composite comprising: (a) a polyurethane formed by the reaction of(i) one or more isocyanates selected from the group consisting ofdiisocyanates, polyisocyanates, and mixtures thereof, and (ii) one ormore polyols; (b) from 20% to 90% by weight, based on the total weightof the composite, of fly ash comprising 50% or greater by weight, flyash particles having a particle size of from 0.2 micron to 100 microns;and (c) from 1% to 40% by weight, based on the total weight of thecomposite, of a coarse filler material comprising 80% or greater byweight, filler particles having a particle size of from greater than 250microns to 10 mm, wherein the weight ratio of the fly ash to the coarsefiller material is from 9:1 to 200:1.
 2. The composite of claim 1,wherein the particle size of the 80% or greater by weight, fillerparticles is from greater than 500 microns to 1 mm.
 3. The composite ofclaim 1, wherein the particle size of the 80% or greater by weight,filler particles is from 300 microns to 500 microns.
 4. (canceled) 5.The composite of claim 1, wherein the coarse filler material includessilica sand, silica fume, cement, slag, metakaolin, talc, mica,wollastonite, limestone, calcium carbonate, perlite, clay, shale,ceramic, glass, seed hull, organic waste, or combinations thereof. 6.(canceled)
 7. (canceled)
 8. (canceled)
 9. (canceled)
 10. The compositeof claim 1, further comprising a fiber material, wherein the fibermaterial is present in an amount of from 1% to 20% by weight, based onthe total weight of the composite.
 11. (canceled)
 12. The composite ofclaim 9, wherein the fiber material includes a plurality of glassfibers.
 13. (canceled)
 14. (canceled)
 15. The composite of claim 1,wherein the fly ash is present in an amount of from 50% to 80% byweight, based on the total weight of the composite.
 16. (canceled) 17.The composite of claim 1, wherein the fly ash has a particle sizedistribution comprising a first mode having a median particle diameterfrom 0.3 micron to 1 micron, a second mode having a median particlediameter from 10 microns to 25 microns, and a third mode having a medianparticle diameter from 40 microns to 80 microns.
 18. The composite ofclaim 17, wherein the weight ratio of the fly ash to the coarse fillermaterial is from 9:1 to 150:1.
 19. (canceled)
 20. (canceled) 21.(canceled)
 22. (canceled)
 23. The composite of claim 1, wherein thecomposite has a density of from 5 lb/ft³ to 70 lb/ft³.
 24. (canceled)25. (canceled)
 26. A building material comprising the composite ofclaim
 1. 27. (canceled)
 28. A composite comprising: (a) from 15% to 60%by weight, based on the total weight of the composite, of a polyurethaneformed by the reaction of (i) one or more isocyanates selected from thegroup consisting of diisocyanates, polyisocyanates, and mixturesthereof, and (ii) one or more polyols; (b) from 20% to 80% by weight,based on the total weight of the composite, of Class C fly ash having aparticle size distribution comprising a first mode having a medianparticle diameter from 0.3 micron to 1 micron, a second mode having amedian particle diameter from 10 microns to 25 microns, and a third modehaving a median particle diameter from 40 microns to 80 microns; (c)from 1% to 40% by weight, based on the total weight of the composite, ofa coarse filler material comprising 80% or greater by weight, fillerparticles having a particle size of from 250 microns to 10 mm, and (d)from 1% to 20% by weight, based on the total weight of the composite, ofa glass fiber material, wherein the weight ratio of the fly ash to thecoarse filler material is from 9:1 to 200:1.
 29. The composite of claim28, wherein the particle size of the 80% or greater by weight, fillerparticles is from 300 microns to 1 mm.
 30. (canceled)
 31. The compositeof claim 28, wherein the coarse filler material includes silica sand,silica fume, cement, slag, metakaolin, talc, mica, wollastonite,limestone, calcium carbonate, perlite, clay, shale, ceramic, glass, seedhull, organic waste, or combinations thereof.
 32. The composite of claim28, further comprising a fiber material selected from polyacrylonitrilefibers, polyamide fibers, polyester fibers, glass fibers, mineral wool,rayon, cellulose, wood fiber, saw dust, wood shavings, cotton, lint,polypropylene fibers, polyethylene fibers, polyacrylic fibers, orcombinations thereof.
 33. (canceled)
 34. The composite of claim 28,wherein the weight ratio of the Class C fly ash to the coarse fillermaterial is from 9:1 to 150:1.
 35. (canceled)
 36. A method of making apolyurethane composite comprising: (a) mixing (1) one or moreisocyanates selected from the group consisting of diisocyanates,polyisocyanates, and mixtures thereof, (2) one or more polyols, (3) 20%to 90% by weight, based on the total weight of the composite, of fly ashcomprising 50% or greater by weight, fly ash particles having a particlesize of from 0.2 micron to 100 microns, and (4) 1% to 40% by weight,based on the total weight of the composite, of a coarse filler materialcomprising 80% or greater by weight, filler particles having a particlesize of from 250 microns to 10 mm to form a mixture, wherein the weightratio of the fly ash to the coarse filler material is from 9:1 to 200:1;and (b) allowing the one or more isocyanates and the one or more polyolsto react in the presence of the fly ash and the coarse filler materialto form the polyurethane composite.
 37. The method of claim 36, whereinthe mixture further comprises a catalyst.
 38. The method of claim 36,wherein the mixture further includes 1% to 20% by weight, based on thetotal weight of the mixture, of a fiber material.
 39. The method ofclaim 36, wherein the coarse filler material includes silica sand,silica fume, cement, slag, metakaolin, talc, mica, wollastonite,limestone, calcium carbonate, perlite, clay, shale, ceramic, glass, seedhull, organic waste, or combinations thereof.
 40. (canceled) 41.(canceled)